1 | /* |
2 | * Kernel Debugger Architecture Independent Console I/O handler |
3 | * |
4 | * This file is subject to the terms and conditions of the GNU General Public |
5 | * License. See the file "COPYING" in the main directory of this archive |
6 | * for more details. |
7 | * |
8 | * Copyright (c) 1999-2006 Silicon Graphics, Inc. All Rights Reserved. |
9 | * Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved. |
10 | */ |
11 | |
12 | #include <linux/types.h> |
13 | #include <linux/ctype.h> |
14 | #include <linux/kernel.h> |
15 | #include <linux/init.h> |
16 | #include <linux/kdev_t.h> |
17 | #include <linux/console.h> |
18 | #include <linux/string.h> |
19 | #include <linux/sched.h> |
20 | #include <linux/smp.h> |
21 | #include <linux/nmi.h> |
22 | #include <linux/delay.h> |
23 | #include <linux/kgdb.h> |
24 | #include <linux/kdb.h> |
25 | #include <linux/kallsyms.h> |
26 | #include "kdb_private.h" |
27 | |
28 | #define CMD_BUFLEN 256 |
29 | char kdb_prompt_str[CMD_BUFLEN]; |
30 | |
31 | int kdb_trap_printk; |
32 | int kdb_printf_cpu = -1; |
33 | |
34 | static int kgdb_transition_check(char *buffer) |
35 | { |
36 | if (buffer[0] != '+' && buffer[0] != '$') { |
37 | KDB_STATE_SET(KGDB_TRANS); |
38 | kdb_printf("%s" , buffer); |
39 | } else { |
40 | int slen = strlen(buffer); |
41 | if (slen > 3 && buffer[slen - 3] == '#') { |
42 | kdb_gdb_state_pass(buf: buffer); |
43 | strcpy(p: buffer, q: "kgdb" ); |
44 | KDB_STATE_SET(DOING_KGDB); |
45 | return 1; |
46 | } |
47 | } |
48 | return 0; |
49 | } |
50 | |
51 | /** |
52 | * kdb_handle_escape() - validity check on an accumulated escape sequence. |
53 | * @buf: Accumulated escape characters to be examined. Note that buf |
54 | * is not a string, it is an array of characters and need not be |
55 | * nil terminated. |
56 | * @sz: Number of accumulated escape characters. |
57 | * |
58 | * Return: -1 if the escape sequence is unwanted, 0 if it is incomplete, |
59 | * otherwise it returns a mapped key value to pass to the upper layers. |
60 | */ |
61 | static int kdb_handle_escape(char *buf, size_t sz) |
62 | { |
63 | char *lastkey = buf + sz - 1; |
64 | |
65 | switch (sz) { |
66 | case 1: |
67 | if (*lastkey == '\e') |
68 | return 0; |
69 | break; |
70 | |
71 | case 2: /* \e<something> */ |
72 | if (*lastkey == '[') |
73 | return 0; |
74 | break; |
75 | |
76 | case 3: |
77 | switch (*lastkey) { |
78 | case 'A': /* \e[A, up arrow */ |
79 | return 16; |
80 | case 'B': /* \e[B, down arrow */ |
81 | return 14; |
82 | case 'C': /* \e[C, right arrow */ |
83 | return 6; |
84 | case 'D': /* \e[D, left arrow */ |
85 | return 2; |
86 | case '1': /* \e[<1,3,4>], may be home, del, end */ |
87 | case '3': |
88 | case '4': |
89 | return 0; |
90 | } |
91 | break; |
92 | |
93 | case 4: |
94 | if (*lastkey == '~') { |
95 | switch (buf[2]) { |
96 | case '1': /* \e[1~, home */ |
97 | return 1; |
98 | case '3': /* \e[3~, del */ |
99 | return 4; |
100 | case '4': /* \e[4~, end */ |
101 | return 5; |
102 | } |
103 | } |
104 | break; |
105 | } |
106 | |
107 | return -1; |
108 | } |
109 | |
110 | /** |
111 | * kdb_getchar() - Read a single character from a kdb console (or consoles). |
112 | * |
113 | * Other than polling the various consoles that are currently enabled, |
114 | * most of the work done in this function is dealing with escape sequences. |
115 | * |
116 | * An escape key could be the start of a vt100 control sequence such as \e[D |
117 | * (left arrow) or it could be a character in its own right. The standard |
118 | * method for detecting the difference is to wait for 2 seconds to see if there |
119 | * are any other characters. kdb is complicated by the lack of a timer service |
120 | * (interrupts are off), by multiple input sources. Escape sequence processing |
121 | * has to be done as states in the polling loop. |
122 | * |
123 | * Return: The key pressed or a control code derived from an escape sequence. |
124 | */ |
125 | char kdb_getchar(void) |
126 | { |
127 | #define ESCAPE_UDELAY 1000 |
128 | #define ESCAPE_DELAY (2*1000000/ESCAPE_UDELAY) /* 2 seconds worth of udelays */ |
129 | char buf[4]; /* longest vt100 escape sequence is 4 bytes */ |
130 | char *pbuf = buf; |
131 | int escape_delay = 0; |
132 | get_char_func *f, *f_prev = NULL; |
133 | int key; |
134 | static bool last_char_was_cr; |
135 | |
136 | for (f = &kdb_poll_funcs[0]; ; ++f) { |
137 | if (*f == NULL) { |
138 | /* Reset NMI watchdog once per poll loop */ |
139 | touch_nmi_watchdog(); |
140 | f = &kdb_poll_funcs[0]; |
141 | } |
142 | |
143 | key = (*f)(); |
144 | if (key == -1) { |
145 | if (escape_delay) { |
146 | udelay(ESCAPE_UDELAY); |
147 | if (--escape_delay == 0) |
148 | return '\e'; |
149 | } |
150 | continue; |
151 | } |
152 | |
153 | /* |
154 | * The caller expects that newlines are either CR or LF. However |
155 | * some terminals send _both_ CR and LF. Avoid having to handle |
156 | * this in the caller by stripping the LF if we saw a CR right |
157 | * before. |
158 | */ |
159 | if (last_char_was_cr && key == '\n') { |
160 | last_char_was_cr = false; |
161 | continue; |
162 | } |
163 | last_char_was_cr = (key == '\r'); |
164 | |
165 | /* |
166 | * When the first character is received (or we get a change |
167 | * input source) we set ourselves up to handle an escape |
168 | * sequences (just in case). |
169 | */ |
170 | if (f_prev != f) { |
171 | f_prev = f; |
172 | pbuf = buf; |
173 | escape_delay = ESCAPE_DELAY; |
174 | } |
175 | |
176 | *pbuf++ = key; |
177 | key = kdb_handle_escape(buf, sz: pbuf - buf); |
178 | if (key < 0) /* no escape sequence; return best character */ |
179 | return buf[pbuf - buf == 2 ? 1 : 0]; |
180 | if (key > 0) |
181 | return key; |
182 | } |
183 | |
184 | unreachable(); |
185 | } |
186 | |
187 | /* |
188 | * kdb_read |
189 | * |
190 | * This function reads a string of characters, terminated by |
191 | * a newline, or by reaching the end of the supplied buffer, |
192 | * from the current kernel debugger console device. |
193 | * Parameters: |
194 | * buffer - Address of character buffer to receive input characters. |
195 | * bufsize - size, in bytes, of the character buffer |
196 | * Returns: |
197 | * Returns a pointer to the buffer containing the received |
198 | * character string. This string will be terminated by a |
199 | * newline character. |
200 | * Locking: |
201 | * No locks are required to be held upon entry to this |
202 | * function. It is not reentrant - it relies on the fact |
203 | * that while kdb is running on only one "master debug" cpu. |
204 | * Remarks: |
205 | * The buffer size must be >= 2. |
206 | */ |
207 | |
208 | static char *kdb_read(char *buffer, size_t bufsize) |
209 | { |
210 | char *cp = buffer; |
211 | char *bufend = buffer+bufsize-2; /* Reserve space for newline |
212 | * and null byte */ |
213 | char *lastchar; |
214 | char *p_tmp; |
215 | char tmp; |
216 | static char tmpbuffer[CMD_BUFLEN]; |
217 | int len = strlen(buffer); |
218 | int len_tmp; |
219 | int tab = 0; |
220 | int count; |
221 | int i; |
222 | int diag, dtab_count; |
223 | int key, buf_size, ret; |
224 | |
225 | |
226 | diag = kdbgetintenv("DTABCOUNT" , &dtab_count); |
227 | if (diag) |
228 | dtab_count = 30; |
229 | |
230 | if (len > 0) { |
231 | cp += len; |
232 | if (*(buffer+len-1) == '\n') |
233 | cp--; |
234 | } |
235 | |
236 | lastchar = cp; |
237 | *cp = '\0'; |
238 | kdb_printf("%s" , buffer); |
239 | poll_again: |
240 | key = kdb_getchar(); |
241 | if (key != 9) |
242 | tab = 0; |
243 | switch (key) { |
244 | case 8: /* backspace */ |
245 | if (cp > buffer) { |
246 | if (cp < lastchar) { |
247 | memcpy(tmpbuffer, cp, lastchar - cp); |
248 | memcpy(cp-1, tmpbuffer, lastchar - cp); |
249 | } |
250 | *(--lastchar) = '\0'; |
251 | --cp; |
252 | kdb_printf("\b%s \r" , cp); |
253 | tmp = *cp; |
254 | *cp = '\0'; |
255 | kdb_printf(kdb_prompt_str); |
256 | kdb_printf("%s" , buffer); |
257 | *cp = tmp; |
258 | } |
259 | break; |
260 | case 10: /* linefeed */ |
261 | case 13: /* carriage return */ |
262 | *lastchar++ = '\n'; |
263 | *lastchar++ = '\0'; |
264 | if (!KDB_STATE(KGDB_TRANS)) { |
265 | KDB_STATE_SET(KGDB_TRANS); |
266 | kdb_printf("%s" , buffer); |
267 | } |
268 | kdb_printf("\n" ); |
269 | return buffer; |
270 | case 4: /* Del */ |
271 | if (cp < lastchar) { |
272 | memcpy(tmpbuffer, cp+1, lastchar - cp - 1); |
273 | memcpy(cp, tmpbuffer, lastchar - cp - 1); |
274 | *(--lastchar) = '\0'; |
275 | kdb_printf("%s \r" , cp); |
276 | tmp = *cp; |
277 | *cp = '\0'; |
278 | kdb_printf(kdb_prompt_str); |
279 | kdb_printf("%s" , buffer); |
280 | *cp = tmp; |
281 | } |
282 | break; |
283 | case 1: /* Home */ |
284 | if (cp > buffer) { |
285 | kdb_printf("\r" ); |
286 | kdb_printf(kdb_prompt_str); |
287 | cp = buffer; |
288 | } |
289 | break; |
290 | case 5: /* End */ |
291 | if (cp < lastchar) { |
292 | kdb_printf("%s" , cp); |
293 | cp = lastchar; |
294 | } |
295 | break; |
296 | case 2: /* Left */ |
297 | if (cp > buffer) { |
298 | kdb_printf("\b" ); |
299 | --cp; |
300 | } |
301 | break; |
302 | case 14: /* Down */ |
303 | memset(tmpbuffer, ' ', |
304 | strlen(kdb_prompt_str) + (lastchar-buffer)); |
305 | *(tmpbuffer+strlen(kdb_prompt_str) + |
306 | (lastchar-buffer)) = '\0'; |
307 | kdb_printf("\r%s\r" , tmpbuffer); |
308 | *lastchar = (char)key; |
309 | *(lastchar+1) = '\0'; |
310 | return lastchar; |
311 | case 6: /* Right */ |
312 | if (cp < lastchar) { |
313 | kdb_printf("%c" , *cp); |
314 | ++cp; |
315 | } |
316 | break; |
317 | case 16: /* Up */ |
318 | memset(tmpbuffer, ' ', |
319 | strlen(kdb_prompt_str) + (lastchar-buffer)); |
320 | *(tmpbuffer+strlen(kdb_prompt_str) + |
321 | (lastchar-buffer)) = '\0'; |
322 | kdb_printf("\r%s\r" , tmpbuffer); |
323 | *lastchar = (char)key; |
324 | *(lastchar+1) = '\0'; |
325 | return lastchar; |
326 | case 9: /* Tab */ |
327 | if (tab < 2) |
328 | ++tab; |
329 | p_tmp = buffer; |
330 | while (*p_tmp == ' ') |
331 | p_tmp++; |
332 | if (p_tmp > cp) |
333 | break; |
334 | memcpy(tmpbuffer, p_tmp, cp-p_tmp); |
335 | *(tmpbuffer + (cp-p_tmp)) = '\0'; |
336 | p_tmp = strrchr(tmpbuffer, ' '); |
337 | if (p_tmp) |
338 | ++p_tmp; |
339 | else |
340 | p_tmp = tmpbuffer; |
341 | len = strlen(p_tmp); |
342 | buf_size = sizeof(tmpbuffer) - (p_tmp - tmpbuffer); |
343 | count = kallsyms_symbol_complete(prefix_name: p_tmp, max_len: buf_size); |
344 | if (tab == 2 && count > 0) { |
345 | kdb_printf("\n%d symbols are found." , count); |
346 | if (count > dtab_count) { |
347 | count = dtab_count; |
348 | kdb_printf(" But only first %d symbols will" |
349 | " be printed.\nYou can change the" |
350 | " environment variable DTABCOUNT." , |
351 | count); |
352 | } |
353 | kdb_printf("\n" ); |
354 | for (i = 0; i < count; i++) { |
355 | ret = kallsyms_symbol_next(prefix_name: p_tmp, flag: i, buf_size); |
356 | if (WARN_ON(!ret)) |
357 | break; |
358 | if (ret != -E2BIG) |
359 | kdb_printf("%s " , p_tmp); |
360 | else |
361 | kdb_printf("%s... " , p_tmp); |
362 | *(p_tmp + len) = '\0'; |
363 | } |
364 | if (i >= dtab_count) |
365 | kdb_printf("..." ); |
366 | kdb_printf("\n" ); |
367 | kdb_printf(kdb_prompt_str); |
368 | kdb_printf("%s" , buffer); |
369 | } else if (tab != 2 && count > 0) { |
370 | len_tmp = strlen(p_tmp); |
371 | strncpy(p: p_tmp+len_tmp, q: cp, size: lastchar-cp+1); |
372 | len_tmp = strlen(p_tmp); |
373 | strncpy(p: cp, q: p_tmp+len, size: len_tmp-len + 1); |
374 | len = len_tmp - len; |
375 | kdb_printf("%s" , cp); |
376 | cp += len; |
377 | lastchar += len; |
378 | } |
379 | kdb_nextline = 1; /* reset output line number */ |
380 | break; |
381 | default: |
382 | if (key >= 32 && lastchar < bufend) { |
383 | if (cp < lastchar) { |
384 | memcpy(tmpbuffer, cp, lastchar - cp); |
385 | memcpy(cp+1, tmpbuffer, lastchar - cp); |
386 | *++lastchar = '\0'; |
387 | *cp = key; |
388 | kdb_printf("%s\r" , cp); |
389 | ++cp; |
390 | tmp = *cp; |
391 | *cp = '\0'; |
392 | kdb_printf(kdb_prompt_str); |
393 | kdb_printf("%s" , buffer); |
394 | *cp = tmp; |
395 | } else { |
396 | *++lastchar = '\0'; |
397 | *cp++ = key; |
398 | /* The kgdb transition check will hide |
399 | * printed characters if we think that |
400 | * kgdb is connecting, until the check |
401 | * fails */ |
402 | if (!KDB_STATE(KGDB_TRANS)) { |
403 | if (kgdb_transition_check(buffer)) |
404 | return buffer; |
405 | } else { |
406 | kdb_printf("%c" , key); |
407 | } |
408 | } |
409 | /* Special escape to kgdb */ |
410 | if (lastchar - buffer >= 5 && |
411 | strcmp(lastchar - 5, "$?#3f" ) == 0) { |
412 | kdb_gdb_state_pass(buf: lastchar - 5); |
413 | strcpy(p: buffer, q: "kgdb" ); |
414 | KDB_STATE_SET(DOING_KGDB); |
415 | return buffer; |
416 | } |
417 | if (lastchar - buffer >= 11 && |
418 | strcmp(lastchar - 11, "$qSupported" ) == 0) { |
419 | kdb_gdb_state_pass(buf: lastchar - 11); |
420 | strcpy(p: buffer, q: "kgdb" ); |
421 | KDB_STATE_SET(DOING_KGDB); |
422 | return buffer; |
423 | } |
424 | } |
425 | break; |
426 | } |
427 | goto poll_again; |
428 | } |
429 | |
430 | /* |
431 | * kdb_getstr |
432 | * |
433 | * Print the prompt string and read a command from the |
434 | * input device. |
435 | * |
436 | * Parameters: |
437 | * buffer Address of buffer to receive command |
438 | * bufsize Size of buffer in bytes |
439 | * prompt Pointer to string to use as prompt string |
440 | * Returns: |
441 | * Pointer to command buffer. |
442 | * Locking: |
443 | * None. |
444 | * Remarks: |
445 | * For SMP kernels, the processor number will be |
446 | * substituted for %d, %x or %o in the prompt. |
447 | */ |
448 | |
449 | char *kdb_getstr(char *buffer, size_t bufsize, const char *prompt) |
450 | { |
451 | if (prompt && kdb_prompt_str != prompt) |
452 | strscpy(kdb_prompt_str, prompt, CMD_BUFLEN); |
453 | kdb_printf(kdb_prompt_str); |
454 | kdb_nextline = 1; /* Prompt and input resets line number */ |
455 | return kdb_read(buffer, bufsize); |
456 | } |
457 | |
458 | /* |
459 | * kdb_input_flush |
460 | * |
461 | * Get rid of any buffered console input. |
462 | * |
463 | * Parameters: |
464 | * none |
465 | * Returns: |
466 | * nothing |
467 | * Locking: |
468 | * none |
469 | * Remarks: |
470 | * Call this function whenever you want to flush input. If there is any |
471 | * outstanding input, it ignores all characters until there has been no |
472 | * data for approximately 1ms. |
473 | */ |
474 | |
475 | static void kdb_input_flush(void) |
476 | { |
477 | get_char_func *f; |
478 | int res; |
479 | int flush_delay = 1; |
480 | while (flush_delay) { |
481 | flush_delay--; |
482 | empty: |
483 | touch_nmi_watchdog(); |
484 | for (f = &kdb_poll_funcs[0]; *f; ++f) { |
485 | res = (*f)(); |
486 | if (res != -1) { |
487 | flush_delay = 1; |
488 | goto empty; |
489 | } |
490 | } |
491 | if (flush_delay) |
492 | mdelay(1); |
493 | } |
494 | } |
495 | |
496 | /* |
497 | * kdb_printf |
498 | * |
499 | * Print a string to the output device(s). |
500 | * |
501 | * Parameters: |
502 | * printf-like format and optional args. |
503 | * Returns: |
504 | * 0 |
505 | * Locking: |
506 | * None. |
507 | * Remarks: |
508 | * use 'kdbcons->write()' to avoid polluting 'log_buf' with |
509 | * kdb output. |
510 | * |
511 | * If the user is doing a cmd args | grep srch |
512 | * then kdb_grepping_flag is set. |
513 | * In that case we need to accumulate full lines (ending in \n) before |
514 | * searching for the pattern. |
515 | */ |
516 | |
517 | static char kdb_buffer[256]; /* A bit too big to go on stack */ |
518 | static char *next_avail = kdb_buffer; |
519 | static int size_avail; |
520 | static int suspend_grep; |
521 | |
522 | /* |
523 | * search arg1 to see if it contains arg2 |
524 | * (kdmain.c provides flags for ^pat and pat$) |
525 | * |
526 | * return 1 for found, 0 for not found |
527 | */ |
528 | static int kdb_search_string(char *searched, char *searchfor) |
529 | { |
530 | char firstchar, *cp; |
531 | int len1, len2; |
532 | |
533 | /* not counting the newline at the end of "searched" */ |
534 | len1 = strlen(searched)-1; |
535 | len2 = strlen(searchfor); |
536 | if (len1 < len2) |
537 | return 0; |
538 | if (kdb_grep_leading && kdb_grep_trailing && len1 != len2) |
539 | return 0; |
540 | if (kdb_grep_leading) { |
541 | if (!strncmp(searched, searchfor, len2)) |
542 | return 1; |
543 | } else if (kdb_grep_trailing) { |
544 | if (!strncmp(searched+len1-len2, searchfor, len2)) |
545 | return 1; |
546 | } else { |
547 | firstchar = *searchfor; |
548 | cp = searched; |
549 | while ((cp = strchr(cp, firstchar))) { |
550 | if (!strncmp(cp, searchfor, len2)) |
551 | return 1; |
552 | cp++; |
553 | } |
554 | } |
555 | return 0; |
556 | } |
557 | |
558 | static void kdb_msg_write(const char *msg, int msg_len) |
559 | { |
560 | struct console *c; |
561 | const char *cp; |
562 | int cookie; |
563 | int len; |
564 | |
565 | if (msg_len == 0) |
566 | return; |
567 | |
568 | cp = msg; |
569 | len = msg_len; |
570 | |
571 | while (len--) { |
572 | dbg_io_ops->write_char(*cp); |
573 | cp++; |
574 | } |
575 | |
576 | /* |
577 | * The console_srcu_read_lock() only provides safe console list |
578 | * traversal. The use of the ->write() callback relies on all other |
579 | * CPUs being stopped at the moment and console drivers being able to |
580 | * handle reentrance when @oops_in_progress is set. |
581 | * |
582 | * There is no guarantee that every console driver can handle |
583 | * reentrance in this way; the developer deploying the debugger |
584 | * is responsible for ensuring that the console drivers they |
585 | * have selected handle reentrance appropriately. |
586 | */ |
587 | cookie = console_srcu_read_lock(); |
588 | for_each_console_srcu(c) { |
589 | if (!(console_srcu_read_flags(con: c) & CON_ENABLED)) |
590 | continue; |
591 | if (c == dbg_io_ops->cons) |
592 | continue; |
593 | if (!c->write) |
594 | continue; |
595 | /* |
596 | * Set oops_in_progress to encourage the console drivers to |
597 | * disregard their internal spin locks: in the current calling |
598 | * context the risk of deadlock is a bigger problem than risks |
599 | * due to re-entering the console driver. We operate directly on |
600 | * oops_in_progress rather than using bust_spinlocks() because |
601 | * the calls bust_spinlocks() makes on exit are not appropriate |
602 | * for this calling context. |
603 | */ |
604 | ++oops_in_progress; |
605 | c->write(c, msg, msg_len); |
606 | --oops_in_progress; |
607 | touch_nmi_watchdog(); |
608 | } |
609 | console_srcu_read_unlock(cookie); |
610 | } |
611 | |
612 | int vkdb_printf(enum kdb_msgsrc src, const char *fmt, va_list ap) |
613 | { |
614 | int diag; |
615 | int linecount; |
616 | int colcount; |
617 | int logging, saved_loglevel = 0; |
618 | int retlen = 0; |
619 | int fnd, len; |
620 | int this_cpu, old_cpu; |
621 | char *cp, *cp2, *cphold = NULL, replaced_byte = ' '; |
622 | char *moreprompt = "more> " ; |
623 | unsigned long flags; |
624 | |
625 | /* Serialize kdb_printf if multiple cpus try to write at once. |
626 | * But if any cpu goes recursive in kdb, just print the output, |
627 | * even if it is interleaved with any other text. |
628 | */ |
629 | local_irq_save(flags); |
630 | this_cpu = smp_processor_id(); |
631 | for (;;) { |
632 | old_cpu = cmpxchg(&kdb_printf_cpu, -1, this_cpu); |
633 | if (old_cpu == -1 || old_cpu == this_cpu) |
634 | break; |
635 | |
636 | cpu_relax(); |
637 | } |
638 | |
639 | diag = kdbgetintenv("LINES" , &linecount); |
640 | if (diag || linecount <= 1) |
641 | linecount = 24; |
642 | |
643 | diag = kdbgetintenv("COLUMNS" , &colcount); |
644 | if (diag || colcount <= 1) |
645 | colcount = 80; |
646 | |
647 | diag = kdbgetintenv("LOGGING" , &logging); |
648 | if (diag) |
649 | logging = 0; |
650 | |
651 | if (!kdb_grepping_flag || suspend_grep) { |
652 | /* normally, every vsnprintf starts a new buffer */ |
653 | next_avail = kdb_buffer; |
654 | size_avail = sizeof(kdb_buffer); |
655 | } |
656 | vsnprintf(buf: next_avail, size: size_avail, fmt, args: ap); |
657 | |
658 | /* |
659 | * If kdb_parse() found that the command was cmd xxx | grep yyy |
660 | * then kdb_grepping_flag is set, and kdb_grep_string contains yyy |
661 | * |
662 | * Accumulate the print data up to a newline before searching it. |
663 | * (vsnprintf does null-terminate the string that it generates) |
664 | */ |
665 | |
666 | /* skip the search if prints are temporarily unconditional */ |
667 | if (!suspend_grep && kdb_grepping_flag) { |
668 | cp = strchr(kdb_buffer, '\n'); |
669 | if (!cp) { |
670 | /* |
671 | * Special cases that don't end with newlines |
672 | * but should be written without one: |
673 | * The "[nn]kdb> " prompt should |
674 | * appear at the front of the buffer. |
675 | * |
676 | * The "[nn]more " prompt should also be |
677 | * (MOREPROMPT -> moreprompt) |
678 | * written * but we print that ourselves, |
679 | * we set the suspend_grep flag to make |
680 | * it unconditional. |
681 | * |
682 | */ |
683 | if (next_avail == kdb_buffer) { |
684 | /* |
685 | * these should occur after a newline, |
686 | * so they will be at the front of the |
687 | * buffer |
688 | */ |
689 | cp2 = kdb_buffer; |
690 | len = strlen(kdb_prompt_str); |
691 | if (!strncmp(cp2, kdb_prompt_str, len)) { |
692 | /* |
693 | * We're about to start a new |
694 | * command, so we can go back |
695 | * to normal mode. |
696 | */ |
697 | kdb_grepping_flag = 0; |
698 | goto kdb_printit; |
699 | } |
700 | } |
701 | /* no newline; don't search/write the buffer |
702 | until one is there */ |
703 | len = strlen(kdb_buffer); |
704 | next_avail = kdb_buffer + len; |
705 | size_avail = sizeof(kdb_buffer) - len; |
706 | goto kdb_print_out; |
707 | } |
708 | |
709 | /* |
710 | * The newline is present; print through it or discard |
711 | * it, depending on the results of the search. |
712 | */ |
713 | cp++; /* to byte after the newline */ |
714 | replaced_byte = *cp; /* remember what/where it was */ |
715 | cphold = cp; |
716 | *cp = '\0'; /* end the string for our search */ |
717 | |
718 | /* |
719 | * We now have a newline at the end of the string |
720 | * Only continue with this output if it contains the |
721 | * search string. |
722 | */ |
723 | fnd = kdb_search_string(searched: kdb_buffer, searchfor: kdb_grep_string); |
724 | if (!fnd) { |
725 | /* |
726 | * At this point the complete line at the start |
727 | * of kdb_buffer can be discarded, as it does |
728 | * not contain what the user is looking for. |
729 | * Shift the buffer left. |
730 | */ |
731 | *cphold = replaced_byte; |
732 | strcpy(p: kdb_buffer, q: cphold); |
733 | len = strlen(kdb_buffer); |
734 | next_avail = kdb_buffer + len; |
735 | size_avail = sizeof(kdb_buffer) - len; |
736 | goto kdb_print_out; |
737 | } |
738 | if (kdb_grepping_flag >= KDB_GREPPING_FLAG_SEARCH) { |
739 | /* |
740 | * This was a interactive search (using '/' at more |
741 | * prompt) and it has completed. Replace the \0 with |
742 | * its original value to ensure multi-line strings |
743 | * are handled properly, and return to normal mode. |
744 | */ |
745 | *cphold = replaced_byte; |
746 | kdb_grepping_flag = 0; |
747 | } |
748 | /* |
749 | * at this point the string is a full line and |
750 | * should be printed, up to the null. |
751 | */ |
752 | } |
753 | kdb_printit: |
754 | |
755 | /* |
756 | * Write to all consoles. |
757 | */ |
758 | retlen = strlen(kdb_buffer); |
759 | cp = (char *) printk_skip_headers(buffer: kdb_buffer); |
760 | if (!dbg_kdb_mode && kgdb_connected) |
761 | gdbstub_msg_write(s: cp, len: retlen - (cp - kdb_buffer)); |
762 | else |
763 | kdb_msg_write(msg: cp, msg_len: retlen - (cp - kdb_buffer)); |
764 | |
765 | if (logging) { |
766 | saved_loglevel = console_loglevel; |
767 | console_loglevel = CONSOLE_LOGLEVEL_SILENT; |
768 | if (printk_get_level(buffer: kdb_buffer) || src == KDB_MSGSRC_PRINTK) |
769 | printk("%s" , kdb_buffer); |
770 | else |
771 | pr_info("%s" , kdb_buffer); |
772 | } |
773 | |
774 | if (KDB_STATE(PAGER)) { |
775 | /* |
776 | * Check printed string to decide how to bump the |
777 | * kdb_nextline to control when the more prompt should |
778 | * show up. |
779 | */ |
780 | int got = 0; |
781 | len = retlen; |
782 | while (len--) { |
783 | if (kdb_buffer[len] == '\n') { |
784 | kdb_nextline++; |
785 | got = 0; |
786 | } else if (kdb_buffer[len] == '\r') { |
787 | got = 0; |
788 | } else { |
789 | got++; |
790 | } |
791 | } |
792 | kdb_nextline += got / (colcount + 1); |
793 | } |
794 | |
795 | /* check for having reached the LINES number of printed lines */ |
796 | if (kdb_nextline >= linecount) { |
797 | char ch; |
798 | |
799 | /* Watch out for recursion here. Any routine that calls |
800 | * kdb_printf will come back through here. And kdb_read |
801 | * uses kdb_printf to echo on serial consoles ... |
802 | */ |
803 | kdb_nextline = 1; /* In case of recursion */ |
804 | |
805 | /* |
806 | * Pause until cr. |
807 | */ |
808 | moreprompt = kdbgetenv("MOREPROMPT" ); |
809 | if (moreprompt == NULL) |
810 | moreprompt = "more> " ; |
811 | |
812 | kdb_input_flush(); |
813 | kdb_msg_write(msg: moreprompt, strlen(moreprompt)); |
814 | |
815 | if (logging) |
816 | printk("%s" , moreprompt); |
817 | |
818 | ch = kdb_getchar(); |
819 | kdb_nextline = 1; /* Really set output line 1 */ |
820 | |
821 | /* empty and reset the buffer: */ |
822 | kdb_buffer[0] = '\0'; |
823 | next_avail = kdb_buffer; |
824 | size_avail = sizeof(kdb_buffer); |
825 | if ((ch == 'q') || (ch == 'Q')) { |
826 | /* user hit q or Q */ |
827 | KDB_FLAG_SET(CMD_INTERRUPT); /* command interrupted */ |
828 | KDB_STATE_CLEAR(PAGER); |
829 | /* end of command output; back to normal mode */ |
830 | kdb_grepping_flag = 0; |
831 | kdb_printf("\n" ); |
832 | } else if (ch == ' ') { |
833 | kdb_printf("\r" ); |
834 | suspend_grep = 1; /* for this recursion */ |
835 | } else if (ch == '\n' || ch == '\r') { |
836 | kdb_nextline = linecount - 1; |
837 | kdb_printf("\r" ); |
838 | suspend_grep = 1; /* for this recursion */ |
839 | } else if (ch == '/' && !kdb_grepping_flag) { |
840 | kdb_printf("\r" ); |
841 | kdb_getstr(buffer: kdb_grep_string, KDB_GREP_STRLEN, |
842 | prompt: kdbgetenv("SEARCHPROMPT" ) ?: "search> " ); |
843 | *strchrnul(kdb_grep_string, '\n') = '\0'; |
844 | kdb_grepping_flag += KDB_GREPPING_FLAG_SEARCH; |
845 | suspend_grep = 1; /* for this recursion */ |
846 | } else if (ch) { |
847 | /* user hit something unexpected */ |
848 | suspend_grep = 1; /* for this recursion */ |
849 | if (ch != '/') |
850 | kdb_printf( |
851 | "\nOnly 'q', 'Q' or '/' are processed at " |
852 | "more prompt, input ignored\n" ); |
853 | else |
854 | kdb_printf("\n'/' cannot be used during | " |
855 | "grep filtering, input ignored\n" ); |
856 | } else if (kdb_grepping_flag) { |
857 | /* user hit enter */ |
858 | suspend_grep = 1; /* for this recursion */ |
859 | kdb_printf("\n" ); |
860 | } |
861 | kdb_input_flush(); |
862 | } |
863 | |
864 | /* |
865 | * For grep searches, shift the printed string left. |
866 | * replaced_byte contains the character that was overwritten with |
867 | * the terminating null, and cphold points to the null. |
868 | * Then adjust the notion of available space in the buffer. |
869 | */ |
870 | if (kdb_grepping_flag && !suspend_grep) { |
871 | *cphold = replaced_byte; |
872 | strcpy(p: kdb_buffer, q: cphold); |
873 | len = strlen(kdb_buffer); |
874 | next_avail = kdb_buffer + len; |
875 | size_avail = sizeof(kdb_buffer) - len; |
876 | } |
877 | |
878 | kdb_print_out: |
879 | suspend_grep = 0; /* end of what may have been a recursive call */ |
880 | if (logging) |
881 | console_loglevel = saved_loglevel; |
882 | /* kdb_printf_cpu locked the code above. */ |
883 | smp_store_release(&kdb_printf_cpu, old_cpu); |
884 | local_irq_restore(flags); |
885 | return retlen; |
886 | } |
887 | |
888 | int kdb_printf(const char *fmt, ...) |
889 | { |
890 | va_list ap; |
891 | int r; |
892 | |
893 | va_start(ap, fmt); |
894 | r = vkdb_printf(src: KDB_MSGSRC_INTERNAL, fmt, ap); |
895 | va_end(ap); |
896 | |
897 | return r; |
898 | } |
899 | EXPORT_SYMBOL_GPL(kdb_printf); |
900 | |